Capillary hydrodynamic fractionation(CHDF) with turbidity detection at a single wavelength is an analytical technique that is often used for sizing the sub-micrometric particles of hydrophobic colloids.This article ...Capillary hydrodynamic fractionation(CHDF) with turbidity detection at a single wavelength is an analytical technique that is often used for sizing the sub-micrometric particles of hydrophobic colloids.This article investigates three sources of errors that affect the particle size distribution(PSD) estimated by CHDF:diameter calibration errors,uncertainties in the particle refractive index(PRI),and instrumental broadening(IB).The study is based on simulated and experimental examples that involve unimodal and bimodal PSDs.Small errors in the diameter calibration curve can produce important deviations in the number average diameter due to systematic shifts suffered by the PSD modes.Moderate uncertainties in the PRI are unimportant in the analysis of unimodal PSDs,but in the specific case of bimodal PSDs,errors in the PRI can strongly affect the estimated number concentration of each mode.The typical IB correction(based on the IB function estimated from narrow standards) produces slightly erroneous average diameters but can lead to PSDs with underestimated widths and distorted shapes.In practice,the three investigated sources of errors can be present simultaneously,and uncertainties in the average diameters,the shape and width of the PSD,and the number concentration of the PSD modes are unavoidable.展开更多
将弯道层流流动形成的Dean涡产生的微粒分离原理运用于污水的2级处理,通过研发水动力分离处理装置,采用投加适量絮凝剂后的某河水进行实验,研究在流道中不同体积流量和絮凝剂含量下装置的分离效果。结果表明:当进水粒径在94.55~161.4μ...将弯道层流流动形成的Dean涡产生的微粒分离原理运用于污水的2级处理,通过研发水动力分离处理装置,采用投加适量絮凝剂后的某河水进行实验,研究在流道中不同体积流量和絮凝剂含量下装置的分离效果。结果表明:当进水粒径在94.55~161.4μm时,分离效果最好;当体积流量小于600 m L/min时,体积流量越大则分离效果越高,而体积流量大于600 m L/min后,分离效果基本不变;在体积流量为600 m L/min时对浊度的去除率在90%以上,对TP和SS去除率分别在85%和50%以上,经装置分离后的清水的浊度大致为1 NTU;在体积流量为600 m L/min时,絮凝剂Fe Cl3的适宜投加质量浓度为21 mg/L。展开更多
基金the financial support from CONICET,Universidad Nacional del Litoral,Universidad Tecnologica Nacional,Secretaria de Politicas Universitarias(Argentina)the financial support from the Basque Government(GV-IT-303-10)Ministerio de Ciencia e Innovacion(MICINN,Ref.CTQ2011-25572)and UPV/EHU(UFI 11/56)
文摘Capillary hydrodynamic fractionation(CHDF) with turbidity detection at a single wavelength is an analytical technique that is often used for sizing the sub-micrometric particles of hydrophobic colloids.This article investigates three sources of errors that affect the particle size distribution(PSD) estimated by CHDF:diameter calibration errors,uncertainties in the particle refractive index(PRI),and instrumental broadening(IB).The study is based on simulated and experimental examples that involve unimodal and bimodal PSDs.Small errors in the diameter calibration curve can produce important deviations in the number average diameter due to systematic shifts suffered by the PSD modes.Moderate uncertainties in the PRI are unimportant in the analysis of unimodal PSDs,but in the specific case of bimodal PSDs,errors in the PRI can strongly affect the estimated number concentration of each mode.The typical IB correction(based on the IB function estimated from narrow standards) produces slightly erroneous average diameters but can lead to PSDs with underestimated widths and distorted shapes.In practice,the three investigated sources of errors can be present simultaneously,and uncertainties in the average diameters,the shape and width of the PSD,and the number concentration of the PSD modes are unavoidable.
文摘将弯道层流流动形成的Dean涡产生的微粒分离原理运用于污水的2级处理,通过研发水动力分离处理装置,采用投加适量絮凝剂后的某河水进行实验,研究在流道中不同体积流量和絮凝剂含量下装置的分离效果。结果表明:当进水粒径在94.55~161.4μm时,分离效果最好;当体积流量小于600 m L/min时,体积流量越大则分离效果越高,而体积流量大于600 m L/min后,分离效果基本不变;在体积流量为600 m L/min时对浊度的去除率在90%以上,对TP和SS去除率分别在85%和50%以上,经装置分离后的清水的浊度大致为1 NTU;在体积流量为600 m L/min时,絮凝剂Fe Cl3的适宜投加质量浓度为21 mg/L。